1. Field of the Invention
The present invention relates to Fe--Cr alloy possessing superior high-temperature characteristics, in particular, a resistance to high-temperature deformation, thermal shock resistance, and high-temperature strength, and a nozzle forming a sub-combustion :chamber nozzle of diesel engines.
2. Background Art
The figure is a longitudinal cross sectional diagram showing a structural outline of a standard diesel engine. According to this type of diesel engine, conventionally, fuel is injected into the sub-combustion chamber from the injection nozzle 2, and this fuel is then ignited by means of spark plug 3. The ignited fuel is then supplied to the combustion chamber formed by means of cylinder block 4 and piston 5 :via nozzle 1 forming the sub-combustion chamber.
Nozzle 1 is formed by means of a forging-worked member of, for example, Fe--Cr alloy and the like. Examples of this type of nozzle can be found by referencing Japanese Patent Application, First Publication, No. Sho 56-96057 and Japanese Patent Application, First Publication, No. Hei 3-115544.
In recent years, there has been a growing demand for high performance and high output diesel engines. Accompanying these demands, the Usage environment of the nozzle forming the nozzle portion of the sub-combustion chamber in the above-mentioned diesel engine has become increasingly strict, as a tendency exists for exposure to environments of even higher temperatures. However, due to the insufficient high-temperature characteristics, in particular, resistance to high-temperature deformation, thermal shock resistance, and high-temperature strength of the nozzle formed by means of conventional Fe--Cr alloys, under severe temperatures greater than conventionally observed, disadvantages exist in that deformation and cracking easily occur and the service life is reached in a comparatively short time.